One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,14)(12,13)(15,16)(18,23)(19,26)(25,29)(28,30) involution — undirected(2,5)(6,8)(17,18,21,23)(19,27,26,32)(20,25,22,29)(24,30,31,28)(10,13)(14,16)(17,19,21,26)(18,24,23,31)(20,28,22,30)(25,32,29,27)(9,11,12,15)(10,14,13,16)(17,18)(19,24)(20,29)(21,23)(22,25)(26,31)(27,28)(30,32)(1,3,4,7)(2,6,5,8)(17,20,21,22)(18,25,23,29)(19,28,26,30)(24,32,31,27)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.